Window and siding replacement in Cottleville
What the code and the permit desk actually require here — and what the houses in Cottleville tend to be hiding behind the siding.
- People
- 5,937
- Homes
- 2,275
- Size
- 4.7 square miles
- From downtown
- About 27 miles west
- ZIP codes
- 63304
First settled in 1798 under a Spanish land grant and platted as a town in 1839, modern Cottleville has been one of Missouri's fastest-growing cities (population grew nearly 1,500% between 1980 and 1990). Its median housing construction year of 2012 makes it by far the newest-built town in this set outside its small historic Old Town core.
Cottleville
The housing here is overwhelmingly new construction -- more than half of all homes (about 52%) were built in the 2010s.
What that vintage turns up
Builder-grade vinyl, installed new with the house, is now twenty-odd years old and arriving at the low end of its range. The frames usually have life left; the sealed units are the part that goes, and they go quietly — a haze that only shows in certain light, then a permanent film between the panes that will not clean off from either side.
Thin builder-grade vinyl shows a consistent pattern: fade on the elevations that get the sun, brittleness with age, and cracking at the nail slots where it was fastened too tight. Vinyl expands half an inch or more across a twelve-foot length, which is why the installation manual asks for about a dime's thickness of play between the fastener head and the siding. Nailed home, it has nowhere to go and it tears at the slot.
The one to watch on a house of this age
OSB sheathing is what is behind most of these walls, and it fails fast once it gets wet — fast enough that people in the trade call it vertical mulch. A small flashing defect that a 1925 house would have shrugged off because its walls dried out through the air leaks will rot a modern insulated wall instead.
Lead paint. No. The lead rule stops at 1978 and this is comfortably clear of it. 25.0% of the homes in St. Charles County were built before 1980, and on anything pre-1978 the EPA renovation rule applies to both of these trades. Window replacement is never exempt from it, at any size — a single window triggers it. A whole-house re-side clears the twenty square foot exterior threshold on the first wall. What the rule actually requires of a contractor.
Neighbourhoods
We work across Old Town Cottleville.
The rules in Cottleville
Siding replacement Permit required
Re-siding is not listed among the exempt work. City Code Sec. 500.298(A)(2) sets out the amended IRC R105.2 exemption list: detached accessory structures under 120 sq ft, retaining walls under 4 ft, water tanks, sidewalks and driveways, painting/papering/tiling/carpeting and similar finish work, small prefabricated pools, playground equipment, window awnings, decks under 200 sq ft with conditions, door and window replacement where the opening size is unchanged, and flatwork. Siding appears nowhere on that list - notable because the list is otherwise detailed and does name windows, so the omission of siding is meaningful rather than an oversight of drafting. Permit therefore required under R105.1 as adopted.
Window replacement, same opening No permit Enlarging or cutting an opening Permit required
Sec. 500.298(A)(2) exempts door and window replacement only 'where the opening size is not increased or decreased.' Like-for-like insert/pocket replacement is exempt; enlarging an opening, reducing it, or cutting a new opening is outside the exemption and requires a permit.
A replacement window here has to be U-0.30 or lower
City Code Chapter 500, Article V, Energy Conservation Code Adopted: 'The International Energy Conservation Code, 2021 Edition, as published by the International Code Council, is hereby adopted as the Energy Conservation Code of the City.' Ordinance No. 2157, 6-26-2024 - the same ordinance that adopted the 2021 IRC at Sec. 500.290. The adopted IRC's own Chapter 11 (N1101-N1104) energy provisions are also carried and amended in Sec. 500.298.
That figure comes from the 2021 edition this jurisdiction has adopted.
A window fitted here must also carry an SHGC of 0.40 or lower.
For comparison, ENERGY STAR asks for U-0.25 or lower with an SHGC of 0.40 or lower everywhere in this metro, which is stricter than every code edition in force here. And the code only bites when the sash and the glazing are replaced together — replace the glass alone in an existing sash, or add a storm window over the top, and it does not apply.
Contractor registration Not published
No contractor licensing or registration article exists in Chapter 500. No trade-licence or business-licence requirement for siding or window contractors was found on the City's Community Development page either. Cottleville is in St. Charles County, whose county contractor licence covers only electricians, plumbers, HVAC, fence installers, pool installers, drainlayers, third-party inspectors and blasters - not siding or windows.
What the permit costs
Chapter 500, Article XI, Sec. 500.330 Fees for Building Plan Reviews and Building Permits: the amounts are set out in 'Exhibit A' / 'Attachment 1 - Building Plan Review and Permit Fees' rather than in the section text. The section does state that 'all fees described in Exhibit A shall entitle the applicant to one initial inspection and one (1) follow-up inspection,' with a $50.00 reinspection fee for any inspection beyond that.
Local quirks
Cottleville's exemption list is the clearest drafting in the St. Charles County group: it explicitly exempts same-opening window and door replacement while conspicuously not exempting siding, so a contractor doing both jobs on one house needs a permit for the siding and none for the windows. Its accessory-structure threshold (120 sq ft) is the lowest in this metro, and it exempts 'window awnings' and 'flatwork' by name. The 2021 IRC adoption carries an unusually long appendix list (A, B, C, E, F, G, H, J, M, N, P). All of it flows from a single 2024 ordinance, No. 2157.
Who to call
- Building dept
- 636-498-6565
- Official
- Not published. Any site printing a name here is guessing.
- Permits
- Department page
How Cottleville compares with the rest of St. Charles County
Same county, same climate, same houses. Not the same rules.
| Place | Permit to re-side | Permit for a window | Window must meet |
|---|---|---|---|
| Cottleville | Yes | No | U-0.30 |
| Lake St. Louis | Yes | Yes | U-0.35 |
| O'Fallon | No | No | U-0.30 |
| St. Charles | No | Not published | U-0.35 |
| St. Peters | Yes | Yes | U-0.30 |
| Wentzville | Yes | Yes | U-0.40 |
Work we have done in Cottleville
Nothing completed in Cottleville so far. Rather than pad this out, we have left it blank until there is a real job to describe.
Where these facts came from
Everything on this page about Cottleville was read off a published source. Where a question has no published answer we have said so rather than filling the gap.
Sources: ecode360.com · ecode360.com · ecode360.com · ecode360.com · ecode360.com · cityofcottleville.com
Getting quotes in Cottleville?
Ask every bidder what the permit and energy rules here are. Then ask us.
Tell us about the house
We answer the phone. If we miss you, we call back.